Printing mechanism for printing a number



Aug. 13, 1957 w. HEINZE ET AL 2,802,415

PRINTING MECHANISM FOR PRINTING A NUMBER, INCLUDING A DECIMAL FRACTION Filed Nov. 17, 1955 Patented Aug. 13, 1957 United States Patent Qtiice PRINTING MECHANISM FOR PRINTING A-NUM- BER, INCLUDING A DECIMAL FRACTION Werner Heinze, Schwerzenbach, and Werner Julicll, Wallisellen, Switzerland, assignors to Precisa A. G. Rechenmaschinenfabrik, Zurich, Switzerland, a firm Our invention relates to a printing mechanism for printing a number including a decimal fraction and, more particularly, to a printing mechanism of this kind for adding or computing machines including means for selecting the denominational position of the decimal mark.

It is an object of our invention to provide simple and efficient means for variably determining the position of the decimal point or other decimal mark to be printed coincidentally to the printing of the number.

It is a more specific object of our invention to equip a plurality of denominational units of the printing mechanism with type bars for printing decimal points, each type bar, if selected for operation, becoming effective by virtue of the momentum imparted to it by the associated digit printing lever without requiring any additional impelling means, such as springs and hammers or the like, a control element of simple construction being provided to select one of the type bars for operation thereby determining the denominational position of the decimal point.

It is a further object of our invention to provide improved means for indicating the selected position of the decimal mark.

Further objects of our invention will appear from a detailed description of a preferred embodiment thereof shown in the accompanying drawings, it being understood that such detailed description serves the purpose of illustrating the invention rather than that of restricting or limiting the same. The features of novelty will be pointed out in the claims.

In the drawings,

Fig. 1 is a transverse vertical section through the printing mechanism of a computing machine illustrating in full lines a type wheel and the associated type bar for the decimal point in retracted position and in dash-dotted lines the type wheel and the type bar in the platen striking position,

Fig. 2 is a view similar to that of Fig. 1 illustrating the platen, the type wheel and the type bar, the latter being in non-selected condition, and the other elements of the printing mechanism being omitted for sake of. clarity,

Fig. 3 is a plan view of a single denominational unit of the printing mechanism shown in Fig. 1, the other denominational units being omitted for sake of clarity,

Fig. 4 is a side view of the printing mechanism shown in Fig. 1 viewed from the left, the platen, parts of the frame and all but two denominational units having been omitted for sake of clarity, and

Fig. 5 is a perspective view of the control element shown in Figs. 1, 2 and 3 and of an indicating mechanism connected therewith indicating the denominational position of the type bar selected for operation by the control element. I a

The printing mechanism of a computing machine shown in the drawings comprises a set of denominational units cooperating with a common paper platen 10, each unit including a mounting plate 11. The plates 11 of the set v position shown in Fig. 1.

are mounted on common frame-rods 12 and 13 in spaced relationship, the frame rods 12 and 13 extending parallel to the platen 10 and being supported'by end plates of the frame (not shown). The mounting plates 11 are held in proper spaced relationship by interposed collars 14 surrounding the rod- 13 and by the engagement of the rearward ends 15 of plates 11 with vertical slots 16 provided in a vertical plate 17 forming part of the frame. Intermediate the frame rods 12 and 13 a pivot pin 18 is riveted in the mounting plate 11. A spring-impelled digit printing lever 19 is fulcrumed on the pivot pin 18, such lever having an upwardly extending arm carrying a pivot pin 20 and having a re'arwardly extending arm guided in a vertical slot- 21 of the frame plate 17 and connected to a helical traction spring 22 anchored to an angle bar 23 secured to plate 17. The upwardly extending arm of lever 19 is slidably guided in a slot 24 of a universal restoring bar 25 which extends across the printing mechanism parallel to the platen 10 and has end arms (not shown) pivotallymounted on pivots disposed coaxially to the pivot pins 18. A type wheel 26 is freely rotatably mounted on the pivot pin 20 and is rigidly connected with a coaxially disposed pinion 27.

Suitable means for rotatably adjusting the type wheels 26 are included in each denominational unit. In the embodiment shown in the drawings, such adjusting means are formed by a gear 28 and an actuating rack 29. The gear 28 is rotatably mounted on a pivot pin 30 secured to the printing lever 19 intermediate the pivot pins 18 and 20. The actuating rack 29 has a slot 31 slidably engaged by a frame rod 32. The rack 29 is in permanent engagement with the gear 28, the point of engagement substantially coinciding with the axis of the pivot pin 18 so that the operative engagement of the rack and the gear will not be adversely all'ected by pivotal movement of the printing lever 19. The tip of the upwardly extending arm of the printing lever 19 is engaged by a downwardly extending lip 33 of a universal locking member 34 pivotally mounted on pivot pins 35 supported by suitable brackets (not shown) fixed to the frame of the machine. The locking member 34 is operative to lock all of the printing levers of the printing mechanism in retracted position contrary to the tendency of the springs 22.

The universal restoring bar 25 is movable by a cam (not shown) between a rearward position shown in Fig. 1 and a forward position in which it has been moved to the left and, therefore, affords liberty of movement to the printing levers 19. The printing operation is initiated by pivotal movement of the universal locking member 34 in clockwise direction causing the lip 33 to release the upper tips of the printing levers 19, whereupon the printing levers impelled by the springs 22 will rock in anti-clockwise direction moving the type wheels 26 into the dashdotted position shown in Fig. 1 in which the selected types strike the paper on the paper platen 10 at the printing point 36 to effect the printing of a number including a decimal fraction, it being understood that the types 37 on the type wheels 26 are digit types. An ink ribbon (not shown) is disposed in front of the printing points 36.

After the printing has been effected by the impact of the type wheels on the paper platen 10, all of the type levers 19 and the type wheels mounted thereon are restored by a clockwise rocking movement of the uniyersal restoring bar 25 returning the elements into the Toward-s the end of their return strokes, cam faces 38 provide at the upper ends of theprinting levers 19 will slide beneath the lip 33 per- 5 tive in each of said positions to obstruct the printing movement of all but a selected one of said printing elements, an indicating member, means for movably mounting said indicating member, an indicating member dial over which said indicating member is movable, and motion transmitting means connecting said control element with said indicating member so as to enable the latter to indicate the denominational position of said selected one of said printing elements.

2. A printing mechanism adapted to print a number including a decimal fraction, comprising a platen, a set of spring impelled digit printing levers, a set of type wheels, each type wheel being carried by one of said levers, means for mounting each of said levers for m0vement of said type wheel in a direction toward and away from a printing point on said platen, means for rotatably adjusting said type wheels, a set of printing elements adapted to print decimal marks, each element being pivotally mounted on one of said levers for relative movement thereto in said direction and adapted to be hurled against said platen by said lever to print a decimal mark adjacent to said printing point, a control element common to all of said printing elements and being selectively movable into any one of a plurality of positions being operative in each of said positions to obstruct the printing movement of all but a selected one of said printing elements, said machine being provided with a window, an indicating member, means for movably mounting the latter in said window, and motion transmitting means connecting said control element with said indicating member to enable the latter to indicate the denominational position of said selected one of said printing elements.

References Cited in the file of this patent UNITED STATES PATENTS 1,197,277 Ellis Sept. 5, 1916 1,371,138 Bair Mar. 8, 1921 1,763,650 Gregory June 17, 1930 1,944,675 Tauschek Jan. 23, 1934 2,416,707 Metzner Mar. 4, 1947 2,550,786 Curtis May l, 1951 

